France elects a new head of state next spring, and this weekend’s (French) Republican primary will be an early test of whether the center-right party will be able to offer a compelling alternative to the reluctant reformism of the Socialist incumbent and the angry nationalism of the far-right National Front. …

Competing for votes is the far-right National Front, whose leader, Marine Le Pen, has tried to soften the party’s image as an outright Fascist outfit. Her platform of economic protectionism, cultural conservatism, anti-Americanism and sympathy for Vladimir Putin seems to resonate with voters fed up with mainstream politicians.

That makes the Republican primary contest between former French President Nicolas Sarkozy and former Prime Minister Alain Juppe—the two lead a pack of seven—all the more significant. As president, Mr. Sarkozy largely failed to deliver on his promises of economic reform and is now stumping for his old job by trying to outdo the National Front in his populist appeal. He promises to cut taxes and loosen the 35-hour workweek but also rails against the European Union and its freedom-of-movement rules.

Then there is Mr. Juppe. He has now drawn a detailed plan for halving the unemployment rate (to 5%). It includes cutting some 250,000 government jobs and €100 billion in public spending, raising the retirement age to 65 from 62, lowering corporate-tax rates and eliminating the wealth tax. France has tried everything, he tells supporters, “except what has worked everywhere else.”